One way to characterize the manner in which information is recorded to and/or read from a date storage medium (e.g., a disk) is the manner in which the head interfaces with the disk. Contact recording has at least been proposed to place the head and disk in direct physical contact when exchanging signals therebetween. Theoretically this maximizes the performance of the head and disk at least in relation to reading information from and writing information to the disk. Certain issues at least potentially exist in relation to contact recording systems. Constant contact between the head and disk may present both wear and contamination (e.g., through generation of particulates) issues. Heat generated by the continuous contact between the head and disk during disk drive operations can also have an adverse effect on the accuracy of the exchange of information between the head and disk (e.g., via thermal transients or asperities). Frictional forces from the contact between the head and disk can also cause data transfer problems in the form of track misregistrations, as well as bit shift or jitter caused by suspension and/or air-bearing resonance excitations.
Another approach which has been utilized in commercial disk drive designs is for the head to fly above the surface of the disk. Typically the head includes a slider with a recording and/or writing element(s) carried thereby. One or more air-bearing surfaces are included on the lower surface of the slider and that project at least generally toward the disk. These air-bearing surfaces are shaped/oriented on the slider body so that the boundary layer of air that is carried by the disk during rotation thereof is compressed and forced to flow underneath the slider. Rotation of the disk in excess of a certain velocity will generate sufficient forces on the air bearing surfaces to lift the slider above the surface of the disk toward which the air-bearing surfaces at least generally project.
Relatively significant development efforts have been directed to the design of the air-bearing surfaces of flying type sliders. The problems that have been addressed by these efforts have not been simply to realize flying of the slider in spaced relation to the disk, but instead to considerations such as attempting to accurately control the fly height or to achieve a consistent fly height. Another area of focus has been to attempt to minimize the spacing between the head and disk during disk drive operations without actually having any significant contact between the slider and the disk, and which may have adverse effects on data transfer operations as well as the operability of the disk drive or components thereof. Reducing the spacing between the head of a flying slider and the corresponding disk is particularly desirable in relation to accommodating higher bit and track densities for the disk.